The Yolk of the Frog Egg

Question

The yolk of the frog egg
A) prevents gastrulation.
B) is concentrated at the animal pole.
C) is homogeneously arranged in the egg.
D) impedes the formation of a primitive streak.
E) supports the higher rate of cleavage at the animal pole compared to the vegetal pole.

Accepted Answer

The yolk of a frog egg is denser and more concentrated at the vegetal pole, which slows down cell division in that region. This results in a higher rate of cleavage at the animal pole, where there is less yolk, allowing cells to divide more rapidly.